Radiative cooling induced coherent maser emission in relativistic plasmas

Area of Science:

• Plasma Physics
• Astrophysics
• Computational Physics

Background:

• Relativistic plasmas in strong electromagnetic fields possess unique properties distinct from classical plasmas.
• These plasmas are fundamental to astrophysical systems like neutron stars, active galactic nuclei, and shocks.
• Experimental and theoretical investigations into relativistic plasmas remain limited.

Purpose of the Study:

• To conduct the first ab initio high-resolution kinetic simulations of relativistic plasmas experiencing synchrotron cooling.
• To investigate the behavior of these plasmas in a highly magnetized medium.

Main Methods:

• Utilized ab initio high-resolution kinetic simulations.
• Modeled relativistic plasmas undergoing synchrotron cooling in a highly magnetized environment.

Main Results:

• Demonstrated spontaneous generation of coherent linearly polarized radiation across a broad parameter range.
• Identified the electron cyclotron maser instability as the mechanism for radiation generation.
• Observed that radiative losses modify the saturation mechanism, enabling prolonged coherent radiation amplification.

Conclusions:

• Relativistic plasmas in strong magnetic fields exhibit fundamentally different behaviors compared to classical plasmas.
• The findings provide insights into astronomical phenomena such as pulsar emission and fast radio bursts.
• The study establishes a new understanding of coherent radiation generation and amplification in astrophysical plasmas.